What Wetlands Are Regulated? Page 13
II. Physical Definition of Wetlands and Waters of the United States
Since wetlands often occur as a transitional zone between uplands (dry land) and open waters, there is a
need to dene the boundaries of wetlands a nd other waters that may be reg ulated under the CWA. Iden-
tifying the physical features that are characteristic of a wetland involves application of a denition that
appears in both Corps and EPA regulations, dening wetlands as:
[A]reas that are inundated or saturated by surf ace or ground water at a frequency and duration sucient to
support, and that under normal circumsta nces do support, a prevalence of vegetation typical ly adapted for life
in saturated soil conditions . Wetlands generally include s wamps, marshes, bogs, and simila r areas.12
is denition is referred to as a “three parameter” test, under which wetlands are characterized by
hydrology (water at or near the surface for a sucient time), hydrophytic vegetation (plants adapted to
saturated soils), and hydric soils (specied soils and conditions). ese three parameters are exhibited on
the ground in myriad physical circumst ances. A wetland, under CWA standards, must exhibit all three of
these characteristics. Locating the boundaries of a wetland on the ground is called wetland delineation.
e regulatory denition of a wetland omits many details. For example, it does not specify how long an
area must be saturated or inundated, how a prevalence of wetland vegetation is measured, or which k inds
of soils can support a wetland ecosystem. To ll in t hese interstices, the federa l agencies have developed a
wetland delineation manual.13 e manual is not designed to be used by laypersons, and consultation with
properly trained experts is recommended.
Neither the regulations nor the delineation manual dene how to determine the boundaries of “other
waters,” such as streams and rivers. Rather, the Corps denition for t he “limits of jurisdiction” provides
that “[i]n the absence of adjacent wetlands, the jurisdiction extends to the ordinary high watermark.”14 e
“ordinary high watermark” is also dened15 and, as a general rule, is not measured by unusual storm events.
While this section addresses physical denitions and features used to identify waters of the United
States, determining legal jurisdiction over those waters can also involve an additional evaluation of physical
factors, as addressed more ful ly in Section III, below.
A. Identifying Wetlands Using the 1987 Corps Delineation Manual and the Regional
Since 1993, EPA and the Corps have both used the 1987 Corps Manual for wetlands delineation.16 While
this 1987 Manua l provides many procedures of uniform application, wetla nds characteristics can vary
across the nation. In 2002, the Corps initiated a process of “regionalization” of wet land delineation pro-
tocols across the countr y.17 e 10 planned Regional Supplements, covering the United States, were com-
pleted in 2012.18 ese Regional Supplements provide specic criteria for wetland delineation (e.g., depth
and duration of groundwater measurements) for use in their part icular regions. To the extent that these
dier from the 1987 Manual, the Regional Supplement will be followed. As a practical matter, delineation
of wetlands will have to follow the Corps Ma nual and the appropriate Regional Supplement.
13. Vcl. Lab. D’ A, T R Y-87-1, C E W D M (1987).
15. 33 C.F.R. §328.3(e)
(noting that the term “ordinary high watermark” “
means that line on the shore established by the uctuations of
water and indicated by physical characters such as clear, natural line impressed on the bank, shelving, changes in the character of soil, destruction
of terrestrial vegetation, the presence of litter and debris, or other appropriate means that consider the characteristics of the surrounding areas”).
16. 58 Fed. Reg. 4995 (Jan. 19, 1993). is announcement ended a long period of controversy over wetland delineation manuals and practices.
After the Corps, EPA and other agencies had presented a new Joint Delineation Manual for use in 1989, there was a signicant controversy
over which delineation manual to use. Many observers felt that the 1989 Manual changed delineation standards signicantly. In an eort to
reduce the controversy, Congress authorized the National Academies of Sciences (NAS) to evaluate the science of wetland delineation. See
Departments of Veterans Aairrs and Housing and Urban Development and Independent Agencies Appropriations Act of 1993, Pub. L. No.
102-389, 106 Stat. 1571 (1992). By the time the NAS released its report in 1995 (see infra note 144), the agencies had withdrawn the 1989
Joint Manual and were using the 1987 Corps Manual.
17. U.S. A C E’, D “R” V C E W D M: I
R (2002), available at http://www.usace.army.mil/Portals/2/docs/civilworks/regulatory/reg_supp/dev_reg_wetlands.pdf.
18. See http://www.usace.army.mil/missions/civilworks/regulatoryprogramandpermits/reg_supp.aspx (last visited Nov. 19, 2012).